SPRUI64F May 2017 – October 2025
Protection diode D2 has the wrong value. It is meant to conduct current, if a voltage too large is connected to the IDK. This current surge should blow the fuse before ICs are damaged. The current part SMCJ26CA is rated for 26 V. It should be replaced with SMCJ5.0A that is rated to protect a 5-V input power supply circuit.